Fuel cell equipped vehicle

ABSTRACT

In a fuel cell equipped vehicle ( 10 ), hydrogen cylinders ( 18 ) storing hydrogen gas to be supplied to a fuel cell battery ( 30 ), a fuel cell ( 30 ), fuel cell accessories ( 31 ), a storage battery ( 40 ), and a PCU ( 50 ) that controls the supply of electric power from the fuel cell ( 30 ) and the storage battery ( 40 ) to a front wheels-driving electric motor ( 14 ) and a rear wheels-driving electric motor ( 16 ) are arranged in that order under a floor of a passenger compartment (R 1 ). Therefore, these major component devices do not reduce the spaces of a passenger compartment (R 1 ), a forward compartment (R 2 ), and a rearward compartment (R 3 ). Since the component devices disposed under the floor of the passenger compartment (R 1 ) have relatively great weights, the center of gravity of the vehicle comes to a low position in a central portion of the vehicle, thus achieving good running stability of the vehicle.

FIELD OF THE INVENTION

The invention relates to a fuel cell equipped vehicle.

BACKGROUND OF THE INVENTION

Various fuel cell equipped vehicles in which fuel cells are disposed sothat a reduction of the compartment space is avoided or minimized havebeen proposed. For example, Japanese Patent Application Laid-open No.2001-268720 proposes a vehicle in which a fuel cell battery, a hydrogenstorage alloy tank, fuel cell accessories, and a battery unit arehorizontally arranged immediately under a compartment floor between thefront and rear wheels.

However, Japanese Patent Application Laid-open No. 2001-268720 does notconsider where to dispose an electric power control device (alsoreferred to as “power control unit”) that drives a vehicle-driving motorusing electric power from the fuel cell battery or electric power from astorage battery, and charges the storage battery using power from thefuel cell battery. Therefore, if the electric power control device isdisposed within a compartment of the vehicle, there occur problems. Forexample, the compartment space of the vehicle is reduced, and the centerof gravity of the vehicle cannot be sufficiently lowered.

DISCLOSURE OF THE INVENTION

It is an object of the invention to provide a fuel cell equipped vehiclehaving various component devices, including an electronic control unit,in which the compartment space is not sacrificed and the center ofgravity of the vehicle is appropriately positioned. Another object is toprovide a fuel cell equipped vehicle that allows appropriate connectionbetween component devices.

In accordance with the invention, a fuel cell equipped vehicle includes:a fuel cell that generates electric power through a reaction between afuel gas and an oxidizing gas; a fuel gas tank that stores the fuel gasto be supplied to the fuel cell; a fuel cell accessory that operateswhen the fuel cell generates electric power; a storage battery thatstores electric energy; and an electric power control unit that controlssupply of electric power regarding the fuel cell and the storagebattery. The fuel cell, the fuel gas tank, the fuel cell accessory, thestorage battery, and the electric power control unit are disposed belowa floor of a passenger compartment of the vehicle.

In the above-described fuel cell equipped vehicle of the invention,major component devices, such as the fuel cell, the fuel gas tank, thefuel cell accessory, the storage battery, and the electric power controlunit, are disposed below the floor of the passenger compartment in aconcentrated fashion. Therefore, the major component devices do notreduce the space of a compartment of the vehicle (e.g., a forwardcompartment, a passenger compartment, and a rearward compartment).Furthermore, since the component devices disposed below the floor of thepassenger compartment have relatively great weights, the center ofgravity of the vehicle comes to a low position near the center of thevehicle, thus achieving good running stability of the vehicle.

The fuel cell and the storage battery may be controlled by the electricpower control unit so as to supply electric power to a vehicle-drivingmotor or supply electric power to other vehicle-installed devices (e.g.,an air-conditioner, AV devices, navigation devices, illuminators, etc.).The storage battery may be a secondary battery (e.g., nickel metalhydride storage secondary battery, a nickel-cadmium secondary battery, alithium hydrogen secondary battery, a lead storage battery, etc.), ormay be a capacitor or the like that directly stores electric energy.

In a preferred form of the fuel cell equipped vehicle of the invention,the fuel gas tank, the fuel cell, the storage battery, and the electricpower control unit may be arranged in that written order in alongitudinal direction relative to the vehicle, below the floor of thepassenger compartment. Therefore, since the fuel gas tank and the fuelcell are disposed close to each other, complicated piping for the supplyof the fuel gas from the fuel gas tank to the fuel cell can be avoided.Since the fuel cell, the storage battery and the electric power controlunit are disposed near to one another, complicated wiring for theelectrical connections between these components can be avoided. It ispreferable that the fuel gas tank, the fuel cell, the storage battery,and the electric power control unit be arranged in that order from therear to the front of the vehicle. With this arrangement, the operationof charging the fuel gas tank with the fuel gas can be performed at arearward site on the vehicle, as in conventional fuel cell equippedvehicles.

In another preferred form of the fuel cell equipped vehicle of theinvention, the fuel gas tank, the fuel cell, the electric power controlunit, and the storage battery may be arranged in that written order in alongitudinal direction relative to the vehicle, below the floor of thepassenger compartment. Therefore, since the fuel gas tank and the fuelcell are disposed close to each other, complicated piping for the supplyof the fuel gas from the fuel gas tank to the fuel cell can be avoided.Since the fuel cell, the storage battery and the electric power controlunit are disposed near to one another, complicated wiring for theelectrical connections between these components can be avoided. It ispreferable that the fuel gas tank, the fuel cell, the electric powercontrol unit, and the storage battery be arranged in that order from therear to the front of the vehicle. With this arrangement, the operationof charging the fuel gas tank with the fuel gas can be performed at arearward site on the vehicle, as in conventional fuel cell equippedvehicles.

In still another preferred form of the fuel cell equipped vehicle of theinvention, the fuel cell accessory may be disposed at one or both of aright side and a left side of the fuel cell. Therefore, since the fuelcell accessory that operates at the time of power generation of the fuelcell is disposed close to the fuel cell, complicated piping or the likefor the connection between the fuel cell and the accessory can beavoided. Examples of the fuel cell accessory include an oxidizing gassupplying device that supplies the oxidizing gas to the fuel cell, afuel gas supplying device that supplies the fuel gas to the fuel cell, amass flow controller that adjusts the pressure and the amount of flow ofthe fuel gas to be supplied to the fuel cell, a fuel gas circulatingdevice that supplies the unreacted fuel gas discharged from the fuelcell back to the fuel cell, a cooling water circulating device thatcirculates cooling water through the fuel cell in order to cool the fuelcell, etc.

In a preferred form of the fuel cell equipped vehicle of the invention,the devices disposed below the floor of the passenger compartment may bedisposed so that upper surfaces of the devices are at substantiallyequal heights. This arrangement facilitates a flat design of the floorface of the passenger compartment.

In a preferred form of the fuel cell equipped vehicle of the invention,the devices disposed below the floor of the passenger compartment may bemounted on an upper portion of a generally flat portion of a body frameof the vehicle which extends between a front wheel and a rear wheel.This arrangement allows the devices to be comparatively easily mountedby utilizing the body frame.

In a preferred form of the fuel cell equipped vehicle of the invention,the devices disposed below the floor of the passenger compartment may bedisposed by utilizing a space formed between a right-side frame of abody frame of the vehicle which extends in a longitudinal directionrelative to the vehicle in a right-side portion of the vehicle and aleft-side frame of the body frame which extends in the longitudinaldirection relative to the vehicle in a left-side portion of the vehicle.This arrangement allows the thickness of each device to be increased byan amount corresponding to the height of the body frame, in comparisonwith the arrangement in which the devices are mounted on top of the bodyframe.

In a preferred form of the invention, the fuel cell equipped vehicle mayfurther include a radiator that radiates heat from a cooling water forcooling the fuel cell, and that is disposed on a portion of a body frameof the vehicle which extends between a central portion of the body frameand a forward portion of the body frame. This arrangement will increasethe space of a forward compartment of the vehicle.

In a preferred form of the above-described fuel cell equipped vehicle,the radiator may be disposed so as to lie between two frame rails of thebody frame. This arrangement will increase the space of the forwardcompartment of the vehicle.

In a preferred form of the invention, the fuel cell equipped vehicle mayfurther include at least one of a front wheel-driving electric motor anda rear wheel-driving electric motor. In this construction, the electricpower control unit controls supply of electric power from the fuel celland the storage battery to the at least one of the front wheel-drivingelectric motor and the rear wheel-driving electric motor. Therefore, theinvention can be appropriately applied to a vehicle that runs bysupplying electric power from a fuel cell or a storage battery to anelectric motor.

In a preferred form of the invention, the fuel cell equipped vehicle mayfurther include a gas pipe that supplies the fuel gas from the fuel gastank to the fuel cell, and an electrical wire that conducts electricpower from the fuel cell and the storage battery to the electric powercontrol unit. In this construction, the gas pipe is provided in one of aright-side portion and a left-side portion of the vehicle, and theelectrical wire is provided in another one of the right-side portion andthe left-side portion of the vehicle. This arrangement is favorable formaintenance operations and the like since the gas pipe and the electricwire are laid separately in the right-side portion and the left-sideportion of the vehicle.

In a preferred form of the invention, the fuel cell equipped vehicle mayfurther include a coolant circulator device that circulates a coolantfor cooling the fuel cell. In this construction, a coolant circulationpath of the coolant circulator device and the gas pipe are provided inone of the right-side portion and the left-side portion of the vehicle,and the electrical wire is provided in another one of the right-sideportion and the left-side portion of the vehicle. This arrangement isfavorable for maintenance operations and the like since the gas pipe andthe coolant circulation path are laid apart from the electric wire.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a fuel cell equipped vehicle in accordance withan embodiment of the invention;

FIG. 2 is a schematic sectional view of the fuel cell equipped vehicleof the embodiment;

FIG. 3 is a perspective view of various component devices arranged on abody frame; and

FIG. 4 is a block diagram of the fuel cell equipped vehicle of theembodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

To make the invention more apparent and clear, preferred embodiments ofthe invention will be described with reference to the accompanyingdrawings. FIG. 1 is a schematic plan view of a fuel cell equippedvehicle in accordance with an embodiment of the invention. FIG. 2 is aschematic sectional view of the fuel cell equipped vehicle. FIG. 3 is aperspective view of various component devices arranged on a body frame.FIG. 4 is a block diagram of the fuel cell equipped vehicle.

A fuel cell equipped vehicle 10 of the embodiment, as shown in FIG. 2,has a passenger compartment R1 in which a driver seat, a passenger ornavigator seat and rear seats are disposed, a forward compartment R2provided near front wheels and separated from the passenger compartmentR1 by a dashboard 12, and a rearward compartment R3 provided near rearwheels for use as a luggage compartment or the like.

The fuel cell equipped vehicle 10 has a body frame 20 as shown in FIG.3. The body frame 20 is substantially made up of a pair of frame rails21, 22 spaced from each other in a transverse direction relative to thevehicle and extending in a longitudinal direction relative to thevehicle, a front cross member 23 connecting front portions of the twoframe rails 21, 22, a rear cross member 24 connecting rear portions ofthe frame rails 21, 22, and center cross members 25, 26 connectingcentral portions of the frame rails 21, 22. A central portion 20 a ofthe body frame 20 which extends between the front wheels FW and the rearwheals RW is generally flat. A forward portion 20 b of the body frame 20is curved upward so as to avoid interference with the front wheels FW. Arearward portion 20 c of the body frame 20 is curved upward so as toavoid interference with the rear wheels RW. A front wheels-drivingelectric motor 14 is mounted on the front cross member 23, and a rearwheels driving electric motor 16 is mounted on the rear cross member 24.Hydrogen cylinders 18, a fuel cell battery 30, a storage battery 40, anda power control unit (hereinafter, referred to as “PCU”) 50 are disposedin that order in the direction from the rear to the front of thevehicle, within a space between the flat central portion 20 a of thebody frame 20 and a flat floor face F of the passenger compartment R1.The hydrogen cylinders 18 and the storage battery 40, each extendingacross upper surfaces of the two frame rails 21, 22, are fixed to thebody frame 20 via brackets (not shown). The PCU 50 is laid on or overupper surfaces of the center cross members 25, 26, and is fixed to thebody frame 20 via a bracket (not shown). The fuel cell battery 30 islaid together with fuel cell battery accessories 31 on or over uppersurfaces of cross members (not shown), and is fixed to the body frame 20via a bracket (not shown).

The front wheels-driving electric motor 14 is one of drive power sourcesof the fuel cell equipped vehicle 10. The electric motor 14 is suppliedwith three-phase alternating current converted by the PCU 50 from directcurrent output from the fuel cell battery 30 or the storage battery 40.With the electric power thus supplied, the electric motor 14 generatesrotating drive force to rotate the front wheels FW. The rearwheels-driving electric motor 16, being another drive power source ofthe fuel cell equipped vehicle 10, is supplied with three-phasealternating current converted by the PCU 50 from direct current outputfrom the fuel cell battery 30 or the storage battery 40. With theelectric power thus supplied, the electric motor 16 generates rotatingdrive force to rotate the rear wheels RW.

The hydrogen cylinders 18 are vessels storing a high-pressure compressedhydrogen gas as a fuel gas to be supplied to the fuel cell battery 30.In this embodiment, a plurality of hydrogen cylinders 18 are laid acrossthe gap between the two frame rails 21, 22, in a rearward portion of theflat central portion 20 a of the body frame 20, and are fixed to thebody frame 20 via steel bands (not shown). Each hydrogen cylinder 18 hasan open-close valve 18 a that is used to supply hydrogen gas to the fuelcell battery 30 or charge the cylinder with hydrogen gas when the amountof hydrogen gas remaining becomes small. Each hydrogen cylinder 18 islaid so that the open-close valve 18 a faces the left side of thevehicle.

The fuel cell battery 30 is a well-known solid polymer electrolyte typefuel cell battery, and has a stack structure in which a plurality ofunit cells, i.e., constitutional units, are stacked. The fuel cellbattery 30 functions as an electric power source of high voltage(several hundred V). Each unit cell of the fuel cell battery 30generates an electromotive force as follows. As indicated in FIG. 4,hydrogen gas (fuel gas) from the hydrogen cylinder 18 is subjected toadjustment in pressure and amount of flow by a mass flow controller 32,and is humidified by a humidifier 33, and then is supplied to an anodeof each unit cell. A cathode of each unit cell is supplied with apressure-regulated compressed air (oxidizing gas) from an air compressor34. As a result, predetermined electrochemical reactions progress ineach unit cell to generate electromotive force. More specifically,hydrogen separates into protons and electrons on the anode. The protonsgenerated on the anode migrate through a solid polymer electrolytemembrane, and reach the cathode while the electrons generated on theanode reach the cathode through a wire connected via a load. On thecathode, the protons and the electrons combine with oxygen to formwater. These electrochemical reactions progress to generateelectromotive force.

The fuel cell battery accessories 31 include the mass flow controller32, the humidifier 33, and the air compressor 34 mentioned above, andfurther include a hydrogen gas circulating pump 35 for supplyingunreacted hydrogen gas discharged from the fuel cell battery 30 back tothe fuel cell battery 30, a water pump 36 that circulates fuel cellbattery-cooling water between the fuel cell battery 30 and a heatradiator 39, an FC controller 37 (FC is an abbreviation of fuel cell)that outputs a control signal for controlling the amounts of gassupplied to the fuel cell battery 30 to the mass flow controller 32 andthe air compressor 34 on the basis of values detected by various sensors(not shown), such as the position of an accelerator pedal detected by anaccelerator pedal sensor (not shown), etc. The accessories are containedin an accessory box disposed on the left side of the fuel cell battery30. A gas pipe 19 (see FIG. 1) connecting the hydrogen cylinders 18 andthe mass flow controller 32, and a cooling water circulation path 38(see FIG. 1) connecting the fuel cell battery 30 and the radiator 39 arelaid in a left side portion of the vehicle in a concentrated manner. Asfor the power supply to fuel cell battery accessories 31, a low-voltagebattery (not shown), for example, a 12-V battery, may be used, orhigh-voltage power from the fuel cell battery 30 or the storage battery40 may be converted to a low-voltage power by the PCU 50. Such alow-voltage battery, if employed, may be disposed in a space portion onthe left side of the PCU 50 in the space between the body frame 20 andthe flat floor face F of the passenger compartment R1.

The storage battery 40 has a structure in which a plurality ofwell-known nickel metal hydride storage batteries are connected inseries, and functions as an electric power source of high voltage(several hundred V). The storage battery 40 is controlled by the PCU 50so as to drive the wheels-driving electric motors 14, 16 at the time oflaunching the vehicle, or recover regenerative electric power during adeceleration regeneration operation, or supply assist power to theelectric motors 14, 16 during acceleration of the vehicle, or be chargedvia the fuel cell battery 30 in accordance with the load. The storagebattery 40 is not limited to a nickel metal hydride storage battery, butmay be any type battery as long as the battery is capable ofcharge-discharge operations. For example, the storage battery 40 may bea nickel-cadmium storage battery, a lithium hydrogen storage battery, alead storage battery, or the like, and may also be a capacitor.

The PCU 50 includes a controller portion 52 formed as a logic circuithaving a microcomputer as a central component, and an inverter portion54 for conversion between the high-voltage direct current of the fuelcell battery 30 or the storage battery 40 and the alternating current ofthe wheels-driving electric motors 14, 16. Electric breakers (not shown)are disposed between the fuel cell battery 30 and the PCU 50, andbetween the storage battery 40 and the PCU 50. The controller portion 52of the PCU 50 controls the operations of the inverter portion 54 andeach electric breaker in accordance with the loads on the wheels-drivingelectric motors 14, 16 and the amount of electricity stored in thestorage battery 40 so as to supply electric power generated by the fuelcell battery 30 to the wheels-driving electric motors 14, 16 or thestorage battery 40, or supply electric power stored in the storagebattery 40 to the wheels-driving electric motors 14, 16. For example,when the load on the wheels-driving electric motors 14, 16 is greatduring vehicle acceleration or the like, the wheels-driving electricmotors 14, 16 are supplied with both power generated by the fuel cellbattery 30 and power stored in the storage battery 40. Duringdeceleration or braking or the like, regenerative electric powerobtained from the wheels-driving electric motors 14, 16 is supplied tothe storage battery 40. The electric breakers may be disposed within thecase of the fuel cell battery 30 and the case of the storage battery 40,or may also be disposed within the case of the PCU 50.

As indicated in FIG. 1, electric cables 55, 56 connecting the PCU 50 andthe wheels-driving electric motors 14, 16, an electric cable 57connecting the PCU 50 and the fuel cell battery 30, and an electriccable 58 connecting the PCU 50 and the storage battery 40 are laid in aright-side portion of the vehicle.

In the fuel cell equipped vehicle 10 of the embodiment constructed asdescribed above, major component devices, such as the hydrogen cylinders18, the fuel cell battery 30, the fuel cell battery accessories 31, thestorage battery 40, and the PCU 50, are disposed under the floor of thepassenger compartment R1 in a concentrated fashion. Therefore, thesecomponent devices do not reduce the spaces of the passenger compartmentR1, the forward compartment R2 and the rearward compartment R3.Furthermore, since the component devices disposed under the passengercompartment R1 have relatively great weights, the center of gravity ofthe vehicle comes to a low position near the center of the vehicle, thusachieving good running stability of the vehicle.

Furthermore, the hydrogen cylinders 18, the fuel cell battery 30, thestorage battery 40 and the PCU 50 are disposed in that order in thedirection from the rear to the front of the vehicle, below the floor ofthe passenger compartment R1. Since the hydrogen cylinders 18 and thefuel cell battery 30 are disposed close to each other, complicatedpiping for the supply of hydrogen gas from the hydrogen cylinders 18 tothe fuel cell battery 30 can be avoided. Since the fuel cell battery 30,the storage battery 40 and the PCU 50 are disposed near to one another,complicated wiring for the electrical connections between thesecomponents can be avoided. In addition, the operation of charging thehydrogen cylinders with hydrogen gas can be performed at a rearward siteon the vehicle, as is the case with conventional fuel cell equippedvehicles.

Still further, since the fuel cell battery accessories 31 are disposedat the left side of the fuel cell battery 30 and adjacent to the fuelcell battery 30, complicated piping and the like for the connectionstherebetween can be avoided.

Yet further, since the floor face F of the passenger compartment R1 isgenerally flat, walkthrough between the front seats and the rear seatsin the passenger compartment R1 becomes easy. In addition, when a rearseat is folded, no protrusion appears on the floor face F. Inparticular, it is preferable that the top surfaces of the componentdevices disposed under the floor be at the same height, since thisarrangement will facilitate a flat design of the floor face F of thepassenger compartment R1. To set the top surfaces of the componentdevices at the same height level, all the component devices may beprovided with a fixed height. If the component devices have differentheights, base members may be mounted on the body frame 20 so as toequalize the height levels of the top surfaces of the component devices.

The component devices under the floor of the passenger compartment R1are disposed on top of the generally flat central portion 20 a of thebody frame 20 between the front wheels FW and the rear wheels RW.Therefore, the embodiment comparatively facilitates the mounting of thecomponent devices. For example, in Japanese Patent Application Laid-openNo. 2001-268720, various component devices are first mounted on a tray,and then the tray is connected firmly to a vehicle body. Such a tray isnot needed in this embodiment.

The gas pipe 19 connecting the hydrogen cylinders 18 and the mass flowcontroller 32, and the cooling water circulation path 38 connecting thefuel cell battery 30 and the radiator 39 are laid in a left-side portionof the vehicle in a concentrated fashion. The electric cables 55 to 58connecting the PCU 50 to the wheels-driving electric motors 14, 16, thefuel cell battery 30 and the storage battery 40 are laid in a right-sideportion of the vehicle in a concentrated fashion. This arrangement ofthe embodiment is favorable for maintenance operations and the like.

It should be apparent that the invention is not restricted by theforegoing embodiment, but that the invention may be carried out invarious other manners within the scope of the invention.

For example, although in the foregoing embodiment, the hydrogencylinders 18, the fuel cell battery 30, the storage battery 40 and thePCU 50 are arranged under the floor of the passenger compartment R1 inthat written order in the direction from the rear to the front of thevehicle, it is also possible to arrange the component devices under thefloor of the passenger compartment R1 in the order of the hydrogencylinders 18, the fuel cell battery 30, the PCU 50 and the storagebattery 40 in the direction from the rear to the front of the vehicle.This arrangement also achieves substantially the same advantages as theforegoing embodiment achieves. The component devices may also bearranged in the order of the hydrogen cylinders 18, the fuel cellbattery 30, the storage battery 40 and the PCU 50 in the direction fromthe front to the rear of the vehicle, or in the order of the hydrogencylinders 18, the fuel cell battery 30, the PCU 50 and the storagebattery 40 in the direction from the front to the rear of the vehicle.These arrangements also achieve substantially the same advantages andeffects as the foregoing embodiment, except that the operation ofcharging the hydrogen cylinders 18 with hydrogen gas will be performedat a forward site on the vehicle.

Although in the foregoing embodiment, the component devices under thefloor of the passenger compartment R1 are mounted on top of thegenerally flat central portion 20 a of the body frame 20, the spacebetween the two frame rails 21, 22 of the body frame 20 may also beutilized to dispose the component devices. This arrangement allows thethickness of each component device to be increased by an amountcorresponding to the height of the body frame 20, is therefore useful ifsize reduction of the component devices is difficult, in comparison withthe embodiment in which the component devices are mounted on top of thebody frame 20.

Furthermore, although in the foregoing embodiment, the radiator 39 isdisposed in the forward compartment R2, the radiator 39 may instead bedisposed on a portion (diagonally rising portion) of the body frame 20which extends between the central portion 20 a and the forward portion20 b, or may be laid between the two frame rails 21, 22 of the bodyframe 20. These arrangements increase the space of the forwardcompartment R2. In these arrangements, a hood or the like may beprovided so that the radiator 39 efficiently receives airflow as thefuel cell equipped vehicle 10 runs.

Still further, although in the foregoing embodiment, the fuel cellequipped vehicle 10 is a four-wheel drive vehicle equipped with thefront wheels-driving electric motor 14 and the rear wheels-drivingelectric motor 16, the vehicle may be equipped with only one of themotors 14, 16. The electric motors for driving wheels may be in-wheelmotors.

Furthermore, although the foregoing embodiment adopts the hydrogencylinders 18 as a fuel gas tank, it is also possible to adopt a tankthat employs a hydrogen storage alloy that stores hydrogen at or below apredetermined hydrogen storage temperature and releases hydrogen gasabove the hydrogen storage temperature.

Yet further, although in the foregoing embodiment, both the fuel cellbattery 30 and the storage battery 40 can be used as power sources todrive the two electric motors 14, 16 (including, in terms of control,the case where both the fuel cell battery 30 and the storage battery 40are used to drive the motors 14, 16, and the case where only one of thefuel cell battery 30 and the storage battery 40 is used to drive themotors 14, 16), it is also possible to adopt a construction in whichonly one of the fuel cell battery 30 and the storage battery 40 can beused as a power source to drive the electric motors 14, 16, for example,a construction in which one of the fuel cell battery 30 and the storagebattery 40 is used as a power source to drive the electric motors 14,16, and the other one of the batteries is used as a power source forother devices (e.g., accessories). It is also possible to adopt aconstruction in which a power source other than the batteries 30, 40 isprovided for driving the electric motors 14, 16, and one or both of thebatteries 30, 40 assist the power source. Thus, it is appropriate thatat least one of the fuel cell battery 30 and the storage battery 40 beusable as a power source for the electric motors 14, 16.

In a fuel cell equipped vehicle 10, hydrogen cylinders 18 storinghydrogen gas to be supplied to a fuel cell battery 30, a fuel cell 30,fuel cell accessories 31, a storage battery 40, and a PCU 50 thatcontrols the supply of electric power from the fuel cell 30 and thestorage battery 40 to a front wheels-driving electric motor 14 and arear wheels-driving electric motor 16 are arranged in that order under afloor of a passenger compartment R1. Therefore, these major componentdevices do not reduce the spaces of a passenger compartment R1, aforward compartment R2, and a rearward compartment R3. Since thecomponent devices disposed under the floor of the passenger compartmentR1 have relatively great weights, the center of gravity of the vehiclecomes to a low position in a central portion of the vehicle, thusachieving good running stability of the vehicle.

1-12. (canceled)
 13. A fuel cell equipped vehicle comprising: a fuelcell that generates electric power through a reaction between a fuel gasand an oxidizing gas; a fuel gas tank that stores the fuel gas to besupplied to the fuel cell; a fuel cell accessory that operates when thefuel cell generates electric power; a storage battery that storeselectric energy; and an electric power control unit that controls supplyof electric power regarding the fuel cell and the storage battery,wherein the fuel cell, the fuel gas tank, the fuel cell accessory, thestorage battery, and the electric power control unit are disposed belowa floor of a passenger compartment of the vehicle.
 14. The fuel cellequipped vehicle according to claim 13, wherein the fuel gas tank, thefuel cell, the storage battery, and the electric power control unit arearranged in that written order in a longitudinal direction relative tothe vehicle.
 15. The fuel cell equipped vehicle according to claim 13,wherein the fuel gas tank, the fuel cell, the electric power controlunit, and the storage battery are arranged in that written order in alongitudinal direction relative to the vehicle.
 16. The fuel cellequipped vehicle according to claim 13, wherein the fuel cell accessoryis disposed at one or both of a right side and a left side of the fuelcell.
 17. The fuel cell equipped vehicle according to claim 13, whereinan upper surface of the fuel cell, an upper surface of the fuel gastank, an upper surface of the fuel cell accessory, an upper surface ofthe storage battery, and an upper surface of the electric power controlunit are at substantially equal heights.
 18. The fuel cell equippedvehicle according to claim 13, wherein the fuel cell, the fuel gas tank,the fuel cell accessory, the storage battery, and the electric powercontrol unit are mounted on an upper portion of a generally flat portionof a body frame of the vehicle which extends between a front wheel and arear wheel.
 19. The fuel cell equipped vehicle according to claim 13,wherein the fuel cell, the fuel gas tank, the fuel cell accessory, thestorage battery, and the electric power control unit are disposed in aspace formed between a right-side frame of a body frame of the vehiclewhich extends in a longitudinal direction relative to the vehicle in aright-side portion of the vehicle and a left-side frame of the bodyframe which extends in the longitudinal direction relative to thevehicle in a left-side portion of the vehicle.
 20. The fuel cellequipped vehicle according to claim 13, further comprising a radiatorthat radiates heat from a cooling water for cooling the fuel cell, andthat is disposed on a portion of a body frame of the vehicle whichextends between a central portion of the body frame and a forwardportion of the body frame.
 21. The fuel cell equipped vehicle accordingto claim 20, wherein the radiator is disposed so as to lie between twoframe rails of the body frame.
 22. The fuel cell equipped vehicleaccording to claim 13, further comprising at least one of a frontwheel-driving electric motor and a rear wheel-driving electric motor,wherein the electric power control unit controls supply of electricpower from the fuel cell and the storage battery to the at least one ofthe front wheel-driving electric motor and the rear wheel-drivingelectric motor.
 23. The fuel cell equipped vehicle according to claim13, further comprising: a gas pipe that supplies the fuel gas from thefuel gas tank to the fuel cell; and an electrical wire that conductselectric power from the fuel cell and the storage battery to theelectric power control unit, wherein the gas pipe is provided in one ofa right-side portion and a left-side portion of the vehicle, and theelectrical wire is provided in another one of the right-side portion andthe left-side portion of the vehicle.
 24. The fuel cell equipped vehicleaccording to claim 23, further comprising a coolant circulator devicethat circulates a coolant for cooling the fuel cell, wherein a coolantcirculation path of the coolant circulator device and the gas pipe areprovided in one of the right-side portion and the left-side portion ofthe vehicle, and the electrical wire is provided in another one of theright-side portion and the left-side portion of the vehicle.